Door-check.



No'. 786,532. PATENTED APR. 4, 1905.

' F. STUMPF.

. DOOR` CHECK. APPLIATION FILED JULY 6, 1903.

l ggezsses' mq Ivo. 786,532.

UNITED STATES Intente@ April 4, 1905'.

FRIEDRICH S'IUMPF, OF MUNICH, GERMANY.

DOOR-CHECK.

SPECIFICATION forming part of Letters Patent No. 786,532, dated April 4,1905.

Application sied July 6,1903. serial No 164.399.

T0 (LZZ whom, it muy concern:

Be it knownthatI, FRIEDRICH Sruurnmerchant, a citizen of Germany,residing at Schwanthalerstrasse 17, Munich, Bavaria, Germany, haveinvented certain new and useful Improvements in Door-Checks; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable otheis skilled in the art to whichit appertains to make and use the same.

My invention relates to locks or latches, and has for its object theprovision of means whereby unauthorized opening of the door or tamperingwith the latch is precluded, while affording to authorized persons readycontrol of the same.

My invention is fully illustrated in the accompanying drawings, in whichFigure 1 is a front elevation of the lock. Fig. 2 is a top plan of thelock with relation to the door, and Figs. 3 and 4 are vertical sectionalviews of the lock at rest and under force from without.

Referring to the drawings more in detail, a represents the latch orlocking bar, pivotally mounted by the pin b within the door. The pin I)is squared at its outer end at c and may be engaged and turned by asuitable key. The free end of the latch ct in closing the'door rides upthe inclined face Z of the hook e, secured to the door-jamb, and dropsinto the space behind said hook, as shown in Fig. 3. A pin f may then bepassed through a hole in the guide g above the latch, preventing theoperation of the latch from without by one in possession of a key.

The structure thus far described constitutes a very simple and efficientlock. In order, however, to permit to persons within an inspection ofapplicants for admission without impairing the security of the door, Ihave embodied in the lock other features of construction, which will bereadily understood from Figs. 3 and 4 and from the following'description:

The hook e is formed as a sleeve, slidably mounted on a slottedcylindrical guide-piece m and limited as to longitudinal and rotarymovement by the pin 7c, secured in the hook e and passing through theslot in the guide m.

Within the hollow guide m and abutting against the pin 7c is a coiledspring if, whose function is to hold the hook e yieldingly toward thedoor-jamb.

When the door is at rest, as shown in Fig. 3, it will be seen that thelatch a can be lifted from behind the hook e by hand from within or bymeans of akey from Without. If the door be partially opened, however,the tension of the spring' c' will hold the hook e over the latch a, asshown in Fig. 4, and effectually prevent its disengagement until thedoor be again entirely closed. This arrangement precludes anypossibility of the latch being lifted from without by means of a wire orother device thr`ough the chink of the door and also permits personswithin to partially open the door and identify persons outside the doorwithout impairing the security of the doorfastening, as any attempt touse force from without would only the more tightly hold the hook e overthe latch co.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent of the United States, is#

1. In adoor-check, the combination with a latch, and means for operatingsaid latch, of a movable catch for said latch, and yielding meansoperating upon the catch for holding the same in engagement with thelatch.

2. In a door-check, the combination with a latch pivotally mounted, andmeans for operating said latch from without, of a catch comprising ahook, and yielding means for holding the hook in engagement with thelatch.

3. In a door-check, the combination with a latch pivotally mounted, andmeans for operating said latch from without, of a guide-piece secured tothe door-jamb, a hook slidably mounted on the guide and adapted toengage the latch, and a spring tending to hold the hook in engagementwith the latch when the door is partially ajar.

4. In a door-check, the combination with a latch pivotally mounted onthe door, and means for operating said latch from without, of a slottedguide-piece mounted on the door-jamb, a sleeve-hook slidably mounted onthe guidepiece, a pin carried by the hook and traveling in the slot, anda spring bearing against the IOO ' an unauthorized attempt to open thedoor from without will cause the spring to hold the hook in engagementwith the latch.

6. In a door-check, the combination with a latch and a pin fixed theretoat right angles and journaled in the door, the end of said pin beingaccessible from without and squared for the reception of a key, of aslotted guidef piece mounted on the doorjamb, a hooked sleeve slidablymounted on the guide-piece, a pin carried by the hook and traveling inthe slot, and a spring,r bearing against the pin and the end of theguide, whereby an unauthor- 1 ized attempt to open the door from withoutwill compressthe spring and hold the hook in engagement with the latch.

In testimony whereof I aiiix my signature to this specification in thepresence of two wit- 3 nesses.

FRIEDRICH STUMPF.

Witn esses ANNI LUTHER, GEORG KRNER.

